The nonlinear compression approach seems to suffer from this sampling technique more than the linear one. To elaborate, for the POD approach, we observe that the MSE values of these three cases are approximately one order of magnitude higher than those of the group. However, MSE values become much higher (about two orders of magnitude) than the rest of the testing cases for the AE models. Therefore, one may want to consider adaptive sampling approaches [1]}, [2]}, [3]} when dealing with nonlinear compression models.
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